RFR(S) 8204209: [Graal] Compilation fails during nmethod printing with "assert(bci == 0 || 0 <= bci && bci < code_size()) failed: illegal bci"

[Igor Veresov]

Make hotspot tolerate negative placeholder BCIs that are produced by Graal. 

Should this fix be deemed acceptable I’ll backport it to graal-jvmci-8.

JBS: https://bugs.openjdk.java.net/browse/JDK-8204209
Webrev: http://cr.openjdk.java.net/~iveresov/8204209/webrev/

Thanks,
igor